Standard stick control



M. c. BAUMANN STANDARD STICK CONTROL (July 15' 1924.

Filed Aug. '5. 2 Sheets-Sheet 1 fnueni'u? Juiy 15., 1924.

M. C. BAUMANN STANDARD STICK CONTROL Filed Aug. 5. 1920 2 Sheets-Sheet 2Patente July 15, 1924.

MILTON C. BAUMANN, OF DAYTON, OHIO, ASSIGNOR TO DAYTON-WRIGHT COMPANY,OF DAYTON, OHIO, A CORPORATION OF DELAWARE.

STANDARD STICK CONTROL.

Application filed August a, 1920. Serial No. 400,975.

To all whom it may concern:

Be it known that I, MILTON C. BAUMANN, a citizen of the United States ofAmerica, residing at Dayton, county of Montgomery, State of Ohio, haveinvented certain new and useful Improvements in Standard Stick Controls,of which the following is a full, clear, and exact description.

The present invention relates to improvements in aeroplane controlmechanism and more particularly to the control itself, a p'referred formof which has been chosen as convenient for the purposes of descriptionand explanation.

Among the objects of the invention is an improvement in the mounting ofthe operating lever.

Another object is to provide a control which is capable of retaining thecontrol surfaces of the aeroplane in adjusted position under normalflying conditions.

Still another object is to provide a stand ard form of control which isadapted for substantial duplication in multiple arrangement.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred form of embodiment of the present inventionis clearly shown.

In the drawings:

Fig. 1 is a fragmentary top view of the control mechanism showing theposition of the control in the fuselage of the aeroplane and connectionof the control to the ailerons and elevators.

Fig. 2 is a side view of the control showing the mounting for the leverand elements of the brake.

Fig. 3 is a view, partly in section along the line 33 of Fig. 2 andpartly in elevation, of the control with the elevator masts attached.

Fig. 1 is a top view of the ball showing more particularly the groovestherein.

Fig. 5 is a side View showing an adaptation of the brake to a ruddercontrol and a tandem arrangement of controls.

Fig. 6 shows, diagrammatically, several of the controls operablyconnected.

In the drawings, wherein, as before stated, one preferred embodiment ofthe present invention is illustrated, the numeral 20 refers to anaeroplane, 21 to the control itself as a whole and 22 to a convenienttype of rudder control device (shown in Fig. 5).

The aeroplane has a control mechanism comprising the usual ailerons,elevators and rudder; the control 21 having the operating lever 30,secured to the floor 120 of the aeroplane; means for operably connectingthis control to the ailerons and. elevators; a rudder control device 22;means for 0 erably connecting the control 21 to the ru der control 22;and operating means from the rudder control to the rudder.

Clear distinction should be drawn between the control mechanismdescribed above, the control itself, and the control surfaces whichinclude only the ailerons, elevators and rud- 1 der. For convenience, inthe specification and claims which follow, control is used to refer tothe device itself.

Referring more particularly to Fi 2 and 3, in which the control 21 isclear? illustrated, the operating lever 30 has an improved type ofmounting comprising a sliding yoke mounting having a ball 50, into andthrough which the lower end of the lever extends. Although there may beother satisfactory methods of mounting this lever, for the purposes ofthe present invention it is preferred to do so by the coaction of thethreaded portion 31 of the lever with the threaded portion 52 of theball. The universal joint further comprises the housing 40 and thecranks or sliding yokes 60. In this mounting the lever 30 is fulcrumedby the ball 50 in such a way as to be capable of rocking either about atransverse axis or a fore and aft axis, the extent of which it isdesirable to -govern by the size of the opening 48 in the top of thehousing 40. In the present case this opening is such as to permit anangular movement of about 40 from the vertical, which movement isbelieved ample for permitting any normal control of the ailerons andelevators.

The ball 50 (see Fig. 4), which it has been found preferable toconstruct'of manganese bronze, although other metals may be substituted,has through its center a hole 51, the lower portion of which is providedwith threads 52. Further, it is also provided with circumferentialgrooves 53 and 54, which, when the-ball is in its normal (or neutral)position, are in fore and aft (53) and lateral (54) positions,respectively, and which extend from an upper neck portion 55 to asimilar lower neck portion 56.

The cranks 6O consist of yoke portions 62 and shaft portions 61. Theseyoke portions are adapted to fit slidably in the grooves 53 and 54 sothat their back surfaces do not protrude beyond the outer surface ofball 50. With this sliding fit, a fore and aft motion of the lever inthe aeroplane will impart a full and positive rotary motion to theshafts 61 of the elevator cranks 66, but no motion to the shafts of theaileron cranks 64 and 65, and a lateral motion of the lever will imparta full and positive rotary motion to the shafts of the aileron cranksand no motion to the shafts of the elevator cranks.

The housing 40 shown in section in Fig.

'3 and in aside View in Fig. 2 encloses the ball 50 and the yokeportions 62 and has bearing members 47 for all of the shafts 61. Itcomprises the upper portion 41 and the lower portion 42 with suitablemeans, such as bolts, for securing the two portions together. Anysuitable method of fixing the control in the aeroplane may be used, butit is preferred to accomplish this by means of the upper portion 41 ofthe housing which portion has a shelf 45 adapted to be secured to floor120 of the aeroplane.

The elevator cranks 66 have masts 70 secured to the ends of their shafts61. These masts are connected from their tops and bottoms, by suitablemeans 71, to the elevators in the usual manner (see Fig. 5).

Further reference to Fig. 5 shows an extension tube 111 connected by thejoint 112 to the crank for operating the lever 116. This lever operatescranks 114 in the usual manner thus giving a positive turning motion tothe aileron torque tube 110 and an opposite positive turning motion tothe other torque tube 117 (see Fig. 1). It is to be understood that thisconstitutes only one of the many possible methods of operating theailerons from the crank 65 and is no part of the present application.

That part of the control 21 which comprises the braking means will nowbe described. Operating within the walls of the housing 40 is a plunger90 which comprises a shaft portion 91 having a slot 92, and a bodyportion 93. Thehousing 40 has an extended portion 43 and a guide portion44 which contain the plunger 90.

A frictional member 32 is fixed on the bottom of the lever 30. Althoughseveral different materials will serve satisfactorily, it is preferredto use fiber in cylindrical block form. The preferred method of securingthe lever 30 to the ball 50, hereinbefore described, peumits adjustmentof the lever relative to the ball and consequently to the housing 40.The plunger 90 has its upper surface of concave curvature to correspondwith the curvature of the inner surface of the housing. Thus as thelever 30 is adjusted more deeply within the ball the frictional element32 is caused to coact with the upper surface of the plunger 90 to exerta braking action. The plunger body portion 93 is large to permit contactwith the frictional element 32 for all ordinary positions of the lever30.

Along with the guide 44, an ear 46 on the housing 40 is slotted throughits vertical center line corresponding with the slot 92, to establish aguide for the bell crank 80 which is pivotally mounted in the ear at 82.Thus, in order to coact sufliciently wit-h the plunger 90, the frictionelement 32 must be pushed down by the lever 30 until whatever impedimentthe crank 80 offers is overcome. In this way friction will be caused notonly between the frictional element 32 and the plunger 90 but also, onaccount of a reactive force resulting therefrom, between the ball andthe housing. This frictional effect is suflicient to produce a brakingaction which tends to retain the operating device and consequently theailerons and elevators in adjusted position. It is evident that the samebraking action for the ailerons and elevators may be obtained byeliminating the extended portion 43 and continuing the lower portion 42of the housing 40 to fit the ball 50.

Fig. 5 shows clearly the connection of the braking means to the ruddercontrol 22. The bell crank 80 consists of the arm 84, operated by theplunger 90 and guided in the slot 92, and the arm 83. When the lever 30pushes down on the plunger 90.it causes the bell crank 80 to swing aboutits pivot. As the arm 83 is connected by means of a flexible cable orcord 81 to a brake 86 operating upon the rudder control 22, the swinging of the bell crank 80 will cause this brake to coact with the ruddercontrol to tend to retain the rudder in its adjusted position. It is tobe understood that other methods of imparting the. braking action may!be employed without departing from the spirit of the invention.

The rudder control 22 chosen as convenient for purposes of descriptioncomprises the two levers 101 and 102 having pedals 105 and 106respectively and suitable connecting means 103 to the rudder. The leverpivots or shafts are connected by gears 107 and 108. Either one of theseshafts 104 may have a brake wheel 87 secured to its end opposite to thelever upon which wheel a brake 86 operates.

Thus the braking means tends to retain not only the ailerons andelevators in adjusted position but also the rudder through the medium ofits control device 22. This braking action is desirable for longdistance flying as it relieves the operator of his giving constantattention to the control. The braking effect is of such a degree that itmay be overcome, instantaneously, by the operators strength, when itbecomes necessary, under abnormal conditions, such as faulty or heavyair loads, to change the adjustment of the ailerons and elevators. Byovercoming by strength is meant forcing the lever to take anotherposition without actually releasing it. It may be released quickly,however, by turning the lever 30 in a direction opposite to that causingthe braking action, thus causin the frictional element 32 to releaseitself from contact with the plunger 90.

It will be noted that by constructing the control 21 in substantiallythe form indicated, it is adapted to be used for the purpose of eithersingle, dual or even multiple control arrangement wherein the severaldevices are substantial duplicates. Further reference to Fig. 5 showshow the control 21 may be connected in tandem arrangement with asubstantial duplicate control 23. By means of simple connections, suchas the tube 113 and joints 112, the ailerons may be actuated from thecontrol 23, since the turning motion imparted to its crank 67 isimparted by these connecting means to the crank 64 of the control 21,which crank, through the medium of the ball 50, causes the forward crank65.to turn. By attaching the connecting means 71 from the masts to themasts 72 on control 23 the elevators may be actuated from eithercontrol.

If another rudder control 26 be installed as shown, the rudder brakelever 89 of con trol 23 may be connected to a brake 86 on the ruddercontrol 26 by means of a flexible cable or cord 88, and the connectingmeans 103 may be attached to the levers of the control 26 and continuedtherefrom to the rudder. But if no separate rudder controlbe installed,the connecting means 88 may be connected to lever 80.

It is evident that an number of controls, substantially the dup icatesof control 21, may be connected in tandem by the use of suitable meanssuch as described above.

Referring to Fig. 6 the connecting tubes 119 are adaptable forconnecting the controls 21 and 24 and controls 23 and 25 all substantialduplicates in side to side arrangement for operating the elevators. Apair of flexible cables or cords 118 and the masts 73, of a type similarto masts 70, are adaptable for connecting up these same controls foroperating the ailerons. A similar connection of braking mechanism may beused for connecting controls 24 and 25 as is used for controls 21 and23.

Thus it is evident that any desired numher of these controls may beadded in side to side arrangements by the use of suitable connectingmeans such as described above for controls 21 and 24.

Further it is obvious that any multiple arrangement desired may beobtained by using connecting means such as used between controls 21 and23 and between controls 21 and 24.

The invention, however, is not limited to such connecting means asdescribed, for any suitable means, permitting the connection of controlswhich are substantial duplicates of control 21, may be substituted.

This feature, of being able to connect the control 21 to substantiallyduplicate controls such as control 23 or control 24L so that theailerons and elevators may be actuated by any one of the devices and sothat a braking action may be exerted by any one of the devices to tendto retain the ailerons elevators and rudder in adjusted position undernormal flying conditions, has the advantage, among others, of not onlystandardizing parts but also standardizing the control itself.

Another feature of standardization lies in the fact that for assemblyall the cranks 60 are made the same. The variation which distinguishesthese cranks comes in the method of connecting themto their respectivecontrol elements, namely the ailerons and elevators.

It is thought that the operation of the control is obvious from theabove description and explanation. Further, from this description, it isevident that a control has been devised which is safe, sure andsufficient in operation,.giving positive motion to the ailerons andelevations, which control is simple and compact in structure, havingeliminated links found in previous types of controls, and which iscapable of exerting a braking effect upon the ailerons, elevators andrudder which is sure and sufficient under normal flying conditions.

It is obvious that other types of controls may be devised withoutvarying in any way from the fundamentals of construction set out above.And it is equally obvious that the braking means herein described andclaimed may be used satisfactorily with other types of operatingdevices, or that the operating device herein described and claimed maybe adapted to be used with other types of braking means with equalsatisfaction, without departing from the spirit of the presentinvention.

While the form of mechanism herein shown and described constitutes apreferred form of embodiment of the invention it is to be understoodthat other forms might be adopted, all coming within the scope of theclaims which follow.

1. An aeroplane having braking means adapted to hold ailerons andelevators in adjusted position, and a second braking meanssimultaneously operable with the first named braking means to hold therudder in adjusted position.

2. In control mechanism for aeroplanes, having an operating lever;braking means tending to retain the ailerons, elevators and rudder inadjusted position, said means comprising a frictional member secured tothe lever; means, stationary with respect to the l ver and affordingsurface capable of coclin with the frictional member to secure a brakingaction; and means permitting the adjustment of the frictional member soas to coact with said surface to secure the braking action.

3. A braking means for an operating lever, comprising a frictionalmember secured to the lower end of the lever; a ball housing stationarywith respect to the lever and having means adapted to coact with thefrictional member; a ball operating within the housing and secured tothe lever; and means permitting the adjustment of the lever in and thruthe ball permitting the frictional member to coact with said coactingmeans to secure the braking action.

4. In control mechanism for aeroplanes having a stick control, brakingmeans which tend to retain the ailerons in adjusted position, said meansbeing operable by the rotation of the control stick.

5. In control mechanism for aeroplanes having a stick control, brakingmeans which tend to retain the elevators in adjusted position, saidmeans being operable by the rotation of the controlstick.

6. In control mechanism for aeroplanes having a stick control, brakingmeans which tend to retain the rudder in adjusted position, said meansbeing operable by the rotation of the control stick.

7. In control mechanism for aeroplanes having a stick control, brakingmeans which tend to retain the ailerons and elevators in adjustedposition, said means being operable by the rotation of the controlstick.

8. In control mechanism for aeroplanes having independent rudder'andaileron controls, braking means tending to retain the rudder andailerons in adjusted position,

said braking means having common operat ing means.

9. In control mechanism for aeroplanes having independent rudder andelevator controls, braking means which tend to retain the rudder andelevators in adjusted position, said braking means having commonoperating means.

10. In control mechanism for aeroplanes having a hand lever foractuating the ailerons and elevators, and an independently operatedrudder the combination with the lever, of braking means operable to tendto retain the ailerons, elevators and rudder in adjusted position, saidmeans being operable by the rotation of the hand lever.

11. The combination with an aeroplane of a control having a hand leverfor actuating the ailerons, braking means for the lever, which tends toretain the ailerons in adjusted position, said means being operableby aseparate movement of the hand lever.

12. The combination with an aeroplane of a control having a hand leverfor actuating the elevators, braking means for the lever, which tends toretain the elevators in adjusted position, said means being operable bya separate movement of the hand lever.

13. The combination with an aeroplane of a control having a hand leverfor actuating the ailerons and elevators, and braking means for thelever, which tends to retain the ailerons and elevators in adjustedposition, said means being operable by a separate movement of the handlever.

l-l. In an aeroplane, a plurality of interconnected controls in multiplearrangement, the several controls being substantial duplicates, andcomprising hand levers for actuating the ailerons and elevators, andbraking means for the levers, operable to tend to retain theailerons'and elevators in adjusted position, said braking means beingoperable by a separate movement of the hand lever.

In testimony whereof I hereto afiix my signature.

MILTON C. BAUMANN.

Witnesses:

ROBERT E. SMITH, ALVINA C. LEHMAN.

